Inducing Absent-Mindedness in the Lab

After years of neglect, Piccione and Rubinstein (1997a) re-examined the problem of imperfect recall and its implications for game theory. They introduced the notion of absent-mindedness through a decision-making problem called the absentminded driver's paradox. This simple game precipitated a vigorous discussion with different researchers having strong opinions about whether the paradox actually exists. Alternative interpretations and varied ways to resolve the paradox were suggested. In the hopes of forwarding this debate, we provide a technique to directly test absentmindedness in the laboratory, even though in the past it has been claimed to be impossible to achieve absent-mindedness in a controlled environment. To accomplish this we rely on a technique called divided attention to impair a subject's recollection of previous choices. Our findings indicate that subjects in the experiment suffer from absent-mindedness while still behaving in a rational manner. Our experimental data for the absent-minded driver�s game shows that a substantial number of subjects demonstrate behavior consistent with the paradox.